This invention relates to a part profile input method. More particularly, the present invention is directed to a part profile input method in an NC data creating apparatus in which a part profile is specified by inputting profile elements of a part using arrow keys and NC data are created to perform machining in accordance with the specified part profile.
An automatic programming system is available in which a conversational display and a function key (soft key) display are each presented in accordance with each step of a plurality of data input steps. A function key (soft key) conforming to a prescribed function and appearing on the function key display is pressed to thereby execute processing corresponding to the function. An NC program is prepared using data input while referring to the conversational display.
An automatic programming system of this kind, which will be described with reference to FIG. 6, successively displays predetermined prompt images (the conversational display) on a display screen in accordance with the following steps:
(1) a first step of selecting execution of "AUTOMATIC PROGRAMMING";
(2) a second step of selecting data to be input, or in other words, a data input step to be executed next;
(3) a third step of selecting the material of a blank;
(4) a fourth step of setting surface roughness;
(5) a fifth step of selecting a drawing format;
(6) a sixth step of inputting the blank profile and the dimensions thereof;
(7) a seventh step of inputting a part profile and the dimensions thereof;
(8) an eighth step of inputting the machining reference point and turret position;
(9) a ninth step of selecting a machining process;
(10) a tenth step of selecting a tool and inputting tool data;
(11) an eleventh step of deciding machining conditions;
(12) a twelfth step of inputting cutting direction;
(13) a thirteenth step of inputting cutting limits;
(14) a fourteenth step of inputting whether or not an area is to be cut by the same tool; and
(15) a fifteenth step of computing a tool path (i.e. of preparing NC data).
An operator responds to these prompts by entering the necessary data from a keyboard. Finally, an NC program (NC data) is created using all of the entered data.
In the part profile input step (the seventh step) performed by the NC data creating apparatus, a prompt (ES =) calling for a part profile element is displayed on the display screen, as shown in FIG. 7. In response to this prompt, arrow keys (.uparw., .fwdarw., .dwnarw., .rarw., , , , , , ,), a thread-cutting key, a chamfering key (C key), a rounding key (R key), a grooving key (G key) and a corner-removal key, which are provided on a keyboard, are operated in accordance with the part profile while a design drawing is observed. The part profile is thus input. Whenever a single part profile element is input using an arrow key, a prompt calling for the dimensions of this element is displayed. In resposne to this prompt, dimensions taken from the design drawing are input, whereupon profile element symbols PFS and graphic images PFG of these profile elements appear on the display screen.
For example, when linear elements are input by pressing the arrow keys indicated by .uparw., .fwdarw., .dwnarw., .rarw., , , , , prompts appear calling for the X coordinate (X.sub.E) of the end point of the straight line, the Z coordinate (Z.sub.E) of this end point, whether or not this straight line contacts the preceding profile element or the next profile element, the angle (A) which the straight linen forms with the Z axis, etc. The dimensions written on the drawing are entered in response to these prompts. However, when the prescribed dimensions are not written on the drawing (as in the case of the angle formed with the Z axis, for example), this input is not required.
When a circular arc is input by pressing the arrow keys indicated by and , prompts appear calling for the X and Z coordinates (X.sub.E, Z.sub.E) of the end point of the circular arc, the X and Z coordinates (X.sub.C, Z.sub.C) of the center of the circular arc, the radius R of the circular arc, and whether the arc contacts the preceding profile element or the next profile element. The dimensions written on the drawing are input in response to these prompts.
When chamfering is input by the C key, a prompt calling for the amount of chamfering appears. When rounding is input by the R key, a prompt inquiring about the radius of rounding is displayed. In response, the dimensions are entered in a similar fashion.
When all the profile elements are input, all of the profile element symbols PFS of the part profile of the overall part profile figure PFG are displayed on the display screen.
During a machining operation such as turning, there are cases where all corner portions C1 .about.C5 are provided with a prescribed chamfer or roundness, as shown in FIG. 8(a), or where all the outside corner portions (projecting corners) K1 .about.K3 among the corner portions are provided with a prescribed chamfer or roundness, as shown in FIG. 8(b), or where all inside corner portions S1 .about.S2 are provided with a prescribed chamfer or roundness, as shown in FIG. 8(c). In accordance with the conventional method, chamfering or rounding is designated by pressing the C key or R key each time at every corner portion even in the cases just described. As a result, the operation for inputting the part profile is a troublesome one.
Accordingly, an object of the present invention is to provide a part profile input method in which operability for a part profile inpput is enhanced by designating rounding or chamfering at outside and inside corners in a simple manner.